<!DOCTYPE html>
<html lang="zc-CN">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>

    <script>
        let arr = [1, 2, 3, 4, 5, 6, 8, 9]
        let arr1 = []
        // let arr3 = [2, 4, 6, 8]
        function getSum(array) {
            let num = 0
            let sum = 0
            for (let i = 0; i < array.length; i++) {
                if (array[i] % 2 !== 0) {
                    sum += array[i]
                    arr1.push(array[i])
                    num = sum / arr1.length
                }
            }
            console.log(num);
        }
        getSum(arr)
        // getSum(arr3)

    </script>
</body>

</html>